embryonic development by timeline Flashcards
1
Q
Day 0
A
fertilization by sperm
2
Q
Day 3
A
morula
3
Q
Day 5
A
blastocyst
4
Q
Day 6
A
implantation
5
Q
Within 1 week
A
hCG secretion ebgins after implantation
6
Q
Within 2 week
A
bilaminar disk (epiblast and hypoblast)
7
Q
Within 3 weeks
A
gastrulation forms trilaminar disk. Beginning of primitive streak, notochord forms
8
Q
within 3-8 weeks
A
neural tube formation, organogenesis, high susceptibility to teratogens
9
Q
Week 4
A
heart begins to beat, upper and lower limb buds begin to form
10
Q
Week 8
A
fetal movement, fetus looks like a baby
11
Q
week 10
A
genitalia have differentiated by sex
12
Q
dizygotic
A
dichorionic, diamniotic
13
Q
0-4 days
A
dichorionic, diamniotic (fused or separate placenta possible)
14
Q
4-8 days (morula)
A
monochorionic, diamniotic
15
Q
8-12 days (blastocyst)
A
monochorionic, monoamniotic
